Simple Harmonic Oscillation of Ferromagnetic Vortex Core

Abstract

Here we report a theoretical description of ferromagnetic vortex dynamics. Based on Thiele’s formulation of the Landau-Lifshitz-Gilbert equation, the motion of the vortex core could be described by a function of the vor- tex core position. Under a parabolic potential generated in the circular magnetic patterns, the vortex core showed a circular rotation−namely the gyrotropic motion, which could be described by a 2-dimensional simple harmonic oscillator. The gyrotropic frequency and apparent damping constant were predicted and compared with the values obtained micromagnetic calculation.